The invention relates to liquid crystal disc memories, more particularly relates to erasable optical memories device.
Hitherto there have been known an optical read-only memory device with a reflective surface on which information is written in the form of sequence of depressions. The memory device of this type is expected as promising for applications for audio devices, video appliance and so on. However, information on the device can not be rewritten.
On the other hand it has been proposed, as memory devices capable of being rewritten, magneto-optical memory devices and optical disc memories with chalcogen amorphous semiconductor. The magneto-optical devices, however, must be manufactured using very expensive and rare material and therefore might not be suitable for mass-production. The optical system for the optical disc memory, in turn, is complicated.